Conventionally, there have been known driving support devices which support driving by a driver such as an adaptive cruise control (ACC) control device and a lane keeping assist (LKA) device. Patent Literature 1 discloses a driving support device guide system which guides the startup of a driving support device to a driver when the current traveling state satisfies an operation condition for such a driving support device. In this driving support device guide system, in order to reduce inconvenience for the driver, when a driving support device guided by the system is not used by the driver, the guide of the driving support device is not performed from the next time even when the operation condition is satisfied.
In the driving support device guide system of Patent Literature 1, when the driver rejects the guide of a driving support device, for example, the guide for starting up the driving support device is not performed even under the condition where the driver is forced to travel in a stressful state. As a result, the driving support device remains unused, and the effectiveness of the driving support device which reduces the stress of the driver may not be sufficiently exhibited.